Thiophosphoric acid esters and their production



United States Patent THIOPHOSPHORIC ACID ESTERS AND THEIR PRODUCTION Gerhard Schrader, Wnppertal-Cronenherg, and August Dtirken, Wuppertal-Sonnborn, Germany, assignors to Farbenfabriken Bayer Aktiengesellsehaft, Leverkusen, Germany, a corporation of Germany 1 No Drawing. Application April 17, 1957 Serial No. 653,274

Claims priority, application Germany April 27, 1956 4 Claims. (Cl. 260 -247.1)

The present invention relates"to"and has asits object new and useful thiophosphoric acid esters as well as their preparation. General1y,these esters may be represented by the following formula:

in which R stands for any aliphatic or aromatic'radicals, R and R stand for lower aliphatic radicals (together with N, R and R may also form a cyclic amine which furthermore may contain hetero-atoms, thus yielding a pyrrolidine-, piperidine-, morpholine-, piperazine ringfor the like), R and 11.; stand for aliphatic radicalsespecially lower aliphaticradicals havingfrom l-4-carb'on atoms." Thiophosphoric acid trialkyl esters which contain in one of their alkyl groups a'mercapto alkyl substituent have become known as very eliect-iv'e insecticides during the last years. An outstanding representative of this class is for example demetone, what is O.Q-diethyl-O-ethyl mercapto ethyl thionophosphate.

It has now been found that excellent insecticides of the above shown formula may be obtained by reacting 0.0- dialkyl thionophosphoric acid halides with'l-(subs'tituted amino)-3-(s.ubstituted mercapto)-2-hydrox-y pr'opanes. For better explanation this reaction may be seen from the following scheme using l-(dimethyl-amino)-3-(ethylmercapto) -2-hydroxy propane and O .O-diethyl 'thio' phosphoric acid chloride as reactants:

'ice

. as an alkali metal hydroxide, carbonate or an organic amine such as diethyl amine and the like. Sometimes, the addition of; a small amount of copper powder to the reaction mixture may be advantageous for obtaining betterzresults. Usually the reaction temperature has to be between about room, temperatureand 100 0. especially between about 60.-70 C.

The preparation of the starting materials is .known from the literature or proceeds in an analogous manner to well known reactions. Thus the reaction of epichlorohydrine with mercaptane is known from Nenitzescu and Scarlatescu, Berichte der deutschen chemischen Gesellschaft, vol. 68, page 587 (1935),.or fro-mPollard and Rietz, J. Am. Chem. Soc., vol. 72, page 4000(1950). The further reaction of the mercapto-propylene-oxides with appropriate amines also proceeds according to mercapto groupsin saidcompounds there may-be present also a methyl-mercapto, phenyl-mercapto, p-chlorophenyl-mercapto, p-nitrophenyl-mercapto group and the like.

The reaction generally is carried out iri inert organic solvents such as benzene, toluene; xylene and the like in the presence of an appropriate acid binding agent such known methods and is described e. g. in J. Am. Chem. Soc., vol. 71, page 1478 (1949) from Gilman and Fullhart. If some starting. materials are not described in the above said literature, then their preparation proceeds exactly to the methods described there and using only;

the corresponding molecular amounts, of starting materials without changing the reaction conditions. a

The compounds of the present invention are generally valuable insecticides. and plant-protecting;-agents. They kill pests; such as aphids, flies and mites; and exhibit agvery.

remarkable systemic action, The application. of these. compounds should be carried out; according to the use of other known phosphor insecticides, i'. e.. in dilution of.

solution with. solid or liquid carriers such as chalk,'talc-, bentonite water, alcohols, liquid hydrocarbons, etc. The inventive compounds may further be used; in combination with other knowninsecticidesor pesticides, etc. Effective concentrations of the compounds may vary also; generally, concentrations of 000.01% to 1.0% kill pests e'fiectively. The combinations of the; compounds mayv be sprayed or dusted or otherwise brought incontactwith' pests-or plants .to be protected. They mayalso be; used as. aerosol. Thev compounds of the; present" invention arejof special advantage for combating sucking. insects such as caterpillars. They exhibit also a'very, remarkable acaricidal activity. Furthermore, they may be used especially for combating mosquito larvae.

As a special example for the utility offthe inventive compounds O- (2- [phenyl-mercapto] -1 [dimethylamino methyl] ethyl) 0.0-diethyl thionophosphate is dissolved; in the same amount of acetone. After thee'ad'dition of 30% by weight of benzyl hydroxy diphenyl polyglycol ether (having 15 glycol radicals iiithechain) this solution is diluted with water to a concentration of active ingredient indicated in the table below. The activities arethe following ones:

Mpsquitos- 0.00001 MQSQUiIO larvae 0.0000001 spider mites 0.001 Systemioac'tion on caterpillars 0.1

Example 1 C'aHsO S OHz-N(O'Hs)i cirno 44.5 grams of a thiopropanol derivative ofzthe follovh ing formula amine, boiling point 0.01 mm./ to 91 C.) are dissolved Patented Sept. 16, 1958' in 50 cc. benzene. There are added 34 grams finely powdered dry potassium carbonate and 1.5 grams powdered copper. While stirring there are added within 10 minutes at a temperature of about 60 C. 40 grams diethylthionophosphoric acid chloride. The mixture is stirred for 5 to '7 hours and then the salts are filtered off with suction. The filtrate is shaken thoroughly with a 10% soda solution. The benzene solution is separated and dried with sodium sulphate. The solvent is removed by dis 33 grams of a thiopropanol derivative of the following formula (prepared from ethylmercapto-propyleneoxide and dimethylamine; boiling point 0.01 mm./34) are dissolved in 17 grams pyridine. There are added 30 grams diethylthionophosphoric acid chloride at a temperature of about 30 C. The reaction mixture is stirred for further 14 hours at the same temperature and then it is poured into ice water, which has been acidified with 20 ml. diluted hydrochloric acid. The precipitated oil is taken up in ether and shaken thoroughly with 10% soda solution. Then the etherical layer is separated and dried over sodium sulphate and the ether is removed by distillation in vacuo. There remain 20 grams of yellow coloured water-unsoluble oil, which cannot be distilled even in high vacuo. The newester obtained shows an LD 011 rats orally of 50 mk./kg. 0.01% solutions kill black bean aphids completely. Spider mites can etlectively be combated with a 0.01% solution. The compound has a remarkable systemical eflfect against caterpillars and plants which are sprayed or dusted with a 0.1% solution or extensions are protected against them.

Example 3 48 grams of a tbiopropanol derivitive of the formula OH CzHs (prepared from phenyl-thiopropylene-oxide and diethylamine, boiling point 0.0l/88-89 C.) are dissolved in 60 cc. toluene. There are added 34 grams of a finely powdered dry potassium carbonate and 1.5 grams of powdered copper. While stirring there are added within 10 minutes at a temperature of about 65 C. 40 grams diethylthionophosphoric acid chloride. The mixture is stirred for further 7 hours at a temperature of 65-70 C. and the residue is filtered oil with suction. The filtrate is shaken with 10% soda solution, the toluene layer is dried over sodium sulphate and the solvent is distilled off. in vacuo. There remain 59 grams of the new ester of the formula 4 as a brown oil, which cannot be distilled even in high vacuo. Yield: 73% of the theoretical. Analysis.-Cal.: P=7.91%; S=16.4%; N=3.56%. Found: P=7.71%; S=16.8%; 1 =3.25%.

Example 4 43 grams of a thlopropanol derivative of the formula (prepared from pheuyl-thiopropylene-oxide and piperidine, boiling point 0.01/115-116 C.) are dissolved in cc. toluene. There are added 28.5 grams finely powdered dry potassium carbonate and 1 gram powdered copper. While stirring there are added within 5 minutes at a temperature of about 60 C. 34 grams diethylthionophosphoric acid chloride. The mixture is stirred for further 6-7 hours and the residue is filtered oil? with suction. The filtrate is shaken with 10% soda solution and afterwards with diluted ammonia and the layers then are separated. After drying the toluene solution over sodium sulphate and clearing with carbon black the toluene is;

distilled off in vacuo. There are obtained 44 grams of the new ester of the following formula GzHsO CHr-N as a clear, light red-brown oil, which cannot be distilled even in vacuo. Yield: 65% of the theoretical.

Analysis-Cal; P=7.7%; S=15.90%; N=3.42%. Found; P=7.9%; S=16.27%; N=3.14%.

Example 5 42.8 grams of a thiopropanol derivative of the formula CHz-CHa H Clair-CE:

(prepared from phenyl-thiopropylene-oxide and morpholine, boiling point 0.01/119-120 C.) are dissolved in cc. toluene. There are added 28.5 grams finely powdered dry potassium carbonate and 1 gram powdered copper. While stirring there are added within 10 minutes at a temperature of about 65 C. 34 grams diethylthionophosphoric acid chloride. The mixture is stirred for further 6 hours at a temperature of about 70 C. and the residue is filtered ed with suction. The filtrate v is shaken with aqueous diluted ammonia, the layers are separated and the toluene solution is dried over sodium After distilling off the toluene in vacuo there remain 50.2 grams of the new ester of the formula CHr-CH:

as a yellow oil, which cannot be distilled even in high vacuo. Yield: 74% of the theoretical.

Analysis -Cal: P=7.64%; S=15.78%; N=3.45%. Found: P=7.53%; S=15.64%; N=3.38%.

What we claim is:

'1. A thiophosphoric acid of the formula CHr-S-R in which R stands for a member selected from the group consisting of lower alkyl groups and phenyl radicals in which R stands for a member selected from the group consisting of lower alkyl groups and phenyl radicals,

stands for a member selected from the group consisting of di-lower alkylamino, piperidino and morpholino radi- 6 cals, R and R stand for a member selected from the group consisting of aliphatic radicals having from 14 carbon atoms, which comprises reacting an 0,0-di-lower alkyl thionophosphoric acid halide with a 2-hydroxy propane of the formula /R1 CH2N HO-$H R2 VH2-SR wherein R stands for a member selected from the group consisting of lower alkyl groups and phenyl radicals, and

No references cited. 

1. A THIOPHOSPHORIC ACID OF THE FORMULA 